3D Woven Pi Preform with Integrated Fillets

This proposal's objective is to design and improve the porosity and mechanical properties of 3D woven Pi preforms for the for the aircraft structures manufacturing with Pi joints.  BRM is going to utilize it's expertise and experience in 3D weaving and resin film infusion to reach these objectives.  BRM is going to utilize existing PI preform patent as a base and develop new weave pattern to include built-in Fillets on the Pi preforms where upright legs of the Pi preform meet with the base of the PI. BRM is going to calculate the amount of fiber is needed to built the Fillets and incorporate them in the new weave pattern.  BRM is going to manufacture the built-in Fillets with 0.150" radius.  Having 0.150" radius at the corners will reduce the stress concentration at those locations and improve the Pi preforms mechanical properties. BRM is going to develop new resin film infusion method to improve the porosity of the Pi preforms.  BRM is going to design a new resin infusion tool to impregnate the Pi preform with resin.  New tool will act as a pressure intensifier at those locations to help reduce the porosity of the Pi preforms.  BRM is going to work with a subcontractor, Northrop Grumman Corporation, to test and report the test results of the new Pi preform.